I have used several wood band saws for aluminum over the years. I have had good luck with 10 TPI or higher and 1/4" blade width or less. I have found that a single cut of aluminum makes the blade unsuitable for wood, whereas the blade will continue to cut aluminum for a long time.
Narrower is better for tight curves, wider blades do a better job on straight line cuts. Narrow blades will break easier/sooner than wider blades.
FYI You can also cut thicker (say 0.060 or thicker) aluminum on the table saw with a sharp fine tooth carbide blade. I have used mine to cut up to 2" aluminum. It does dull the blade slightly for wood use thereafter. Feed the material slow and evenly, especially thinner material, with proper push sticks etc.. I also like to cut with the blade high out of the material so the blade is cutting more on the down stroke rather than lateral.